1. Field of the Invention
The present invention relates generally to the field of bookbinding and in particular to binder strips used in binding a stack of sheets to form a bound book.
2. Description of Related Art
Binder strips utilizing heat activated adhesives are commonly used to bind a stack of sheets utilizing a desk top binding machine. A typical binder strip is disclosed in USPNo. 4,496,617, the contents of which are fully incorporated herein by reference. Referring to the drawings, FIG. 1A/B depict such a conventional binder strip 18. One side 18B of the strip, as shown in FIG. 1B includes a layer of heat activated adhesive which is formed on a flexible substrate of paper or plastic. A conventional binding machine operates to apply heat and pressure to the binder strip and to fold the strip around the edge of a stack of sheets to be bound. The adhesive, upon cooling, secures the edges of the sheets together and also to the substrate. Binder strips are available in differing widths to accommodate stacks of differing thickness. A typical binding machine for carrying out the actual binding process is disclosed in U.S. Pat. No. 5,052,873, the contents of which are also fully incorporated herein by reference.
It is frequently desirable to provide descriptive information and other graphics on the printable side 18A of FIG. 1A of the binder strip before a book is bound. Such graphics may include, by way of example, a title, a listing of authors and/or a company logo. U.S. Pat. No. 6,027,265, the contents of which are also fully incorporated herein by reference, discloses a desk top binder strip printing machine capable of printing binder strips. This printing machine is capable of reliably printing binder strips, including strips which have roughly textured surfaces. However, the machine is dedicated to printing binder strips and is significantly more expensive than most desk top printers.
There is a need for a book binding structure which enables the printing of binder strips using conventional, general purpose printers. As will become apparent upon a reading of the following Detailed Description of the Invention together with the drawings, the present invention provides these and other advantages.